Both humans and monkeys rely on visual perception to seek food, find attractive mates, and spot danger. Moreover, we often accomplish these goals in a varied and complex environment. Each of the aforementioned tasks - and dozens of others in our everyday lives - is a visual search task. In these tasks, we scan through a cluttered visual scene to locate and identify objects of interest. While the degree to which scene representation affects search has progressively become clearer from research in cognitive psychology, the neurophysiological mechanisms that underlie scene perception in primates are still poorly understood. Specifically, it is still unknown how scenes are encoded in the brain and how these representations affect attentional guidance during search. This grant aims to reveal the neurophysiological mechanisms that underlie scene search by using a combination of behavioral testing and physiological recording informed by predictions from computational models of attention. Physiological experiments will focus on high level visual areas involved in both object processing (inferior temporal cortex, IT) and in attentional control (the lateral intraparietal area, LIP). Therefore, the specific aims of this project are to: 1) Understand the role of the inferior temporal cortex in scene representation;and 2) Test the hypothesis that scene-related activity in IT serves as a physiological mechanism through which scene contextual cues can bias activity in LIP and guide visual search. These studies will provide important new insights into both the neural representation of complex scene environments and the communication between two brain regions that interact to produce high level vision. The long term goal of this research is to understand how the brain efficiently processes information encountered in the real world so as to potentially restore or augment perceptual processing in individuals with compromised visual systems. PUBLIC HEALTH RELEVANCE: This study will examine the role of two high level visual areas, inferior temporal cortex (IT) and the lateral intraparietal area (LIP), in the guidance of attention during search through naturalistic scenes. The function of these two areas will be studied by using a combination of behavioral testing and neurophysiological recording. The long-term goal of this research is to understand how the brain efficiently processes information encountered in the real world, so as to potentially restore or augment perceptual processing in individuals with compromised visual systems.